According to the American Wind Energy Association (AWEA), Small Wind Turbines (SWT’s) are defined as those having a capacity of 100 kilowatts (KW) or less. Small wind turbines have also been described as turbines with a rated power of less than 10 kW. Many small wind turbines can look like a miniaturized, ‘back yard’ version of the large, utility-scale, three-bladed commercial turbines. With large variations in appearance, the industry encompasses over 200 different models of small wind turbines.
How Are SWT’s Used?
Small wind turbines have traditionally been utilized in marine, farm, cottage and other rural applications where access to the electrical grid is limited. A variety of factors have resulted in small wind turbines being used more frequently in everyday applications. These turbines may also be as small as those used for boating or caravans.
Comparison to Larger Turbines
Small wind turbines often have integral generators, DC current output, shaped blades, and a vane to point into the wind. Larger, more costly turbines have sophisticated gearing, AC current output, and are always aligned with the wind. A small wind turbine can feature a simple, yet effective design, with only two or three moving parts. Residential settings often rely on the smaller wind turbine offerings, while commercial settings meet the demand of the larger turbines for energy generation.
SWT Design Features
There are two main types of small wind turbines: (1) a Horizontal Axis Wind Turbine (HAWT), and (2) a Vertical Axis Wind Turbine (VAWT). The axis refers to the rotational axis of the turbine blades. The HAWT is the more popular option, commonly found in residential and commercial settings. The VAWT is gaining in popularity, because of its quieter operation and insensitivity to wind direction. Most SWT’s feature three blades of 2-15 feet in length, a generator located at the hub, and a tail to orient the turbine in the wind. Small wind turbines are commonly mounted on a steel tower to take advantage of prevailing wind patterns. Basically, a small wind turbine is just a miniature version of larger wind turbines, such as are found in wind farms.
Will a Small Wind Turbine Save Money?
Homes use approximately 9,400 kilowatt-hours (kWh) of electricity per year (about 780 kWh per month). A wind turbine can cut a household electric bill in half. Wind turbine owners can have monthly utility bills that are less than $20 for nine months of the year. The amount of money a small wind turbine saves depends on its cost, electrical usage of the home, and the amount of prevailing wind at the homesite.
Small wind turbines provide a cost-effective, efficient method of generating free electricity from renewable wind energy. These wind turbines can be technologically advanced, yet easy to build and install. DIY small wind turbines are a popular option for homeowners with the skills and tools to build these electrical generators. Small wind turbines can also be purchased, with a large variety available online.